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arXiv · 2006.06524

Observation of a higher-order topological bound state in the continuum

Alexander Cerjan·Marius Jürgensen·Wladimir A. Benalcazar·Sebabrata Mukherjee·Mikael C. Rechtsman
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Abstract

Higher-order topological insulators are a recently discovered class of materials that can possess zero-dimensional localized states regardless of the dimension of the lattice. Here, we experimentally demonstrate that the topological corner-localized modes of higher-order topological insulators can be symmetry protected bound states in the continuum; these states do not hybridize with the surrounding bulk states of the lattice even in the absence of a bulk bandgap. As such, this class of structures has potential applications in confining and controlling light in systems that do not support a complete photonic bandgap.

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Alexander Cerjan, Marius Jürgensen, Wladimir A. Benalcazar, Sebabrata Mukherjee, Mikael C. Rechtsman. 2020-06-11. Observation of a higher-order topological bound state in the continuum. https://doi.org/10.1103/physrevlett.125.213901

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